1. Field of the Invention
The invention is related to the field of communications, and in particular, to transporting signaling over a bearer network for low latency services provided by a wireless communication network.
2. Statement of the Problem
Communication providers are continually improving the services they provide to their customers. Wireless services have become very popular due to the conveniences that they provide to the customers. Wireless services, such as cellular and PCS phones, are common for both personal and business use. Because many communication providers provide the basic cellular or PCS service, these communication providers compete to provide other services that are new and useful.
One service provided by one or more communication providers is Push to Talk (PTT) service. PTT service was initiated by Nextel Communications of Reston, Va. PTT-type services will be referred to herein as Push to Call (PTC) services. Push to Call is a service that allows a subscriber to use their cellular phone like a walkie-talkie. The subscriber simply pushes a button on the phone to quickly connect to one or more other subscribers set up in their group list or “buddy list” maintained in a Push to Call (PTC) server. Some subscribers like the quick connection provided by the PTC service.
One challenge in providing PTC service is that low latency call setup is desired. End-to-end call setup should be about one second or less to provide the walkie-talkie operation that is satisfactory to the subscriber. Low latency call setup may also be desired for other services. Unfortunately, some current wireless communication networks may not be able to provide call setup that is fast enough for services that require low latency call setup.
Wireless communication networks typically include a signaling network and a bearer network. One reason why current wireless communication networks may not be able to provide fast enough call setup is that the signaling network for transporting call setup messages is engineered for capacity and not to provide low latency call setup. The signaling network is engineered to handle as many calls as possible because wireless communication networks provide service to millions of subscribers. One way the signaling network increases capacity is with message bundling. For message bundling, the signaling network buffers multiple signaling messages to a destination before transmitting the messages to the destination. Message bundling can allow the signaling network to handle higher call loads, but may also increase call setup delays. The call setup delays may not be as important in the signaling network because the signaling network transports signaling messages that are generally not real-time critical. The signaling messages may be delayed without a noticeable effect as long as the delay is not exorbitant. Call setup latency for a typical call may be multiple seconds.
Unfortunately, many wireless communication networks are not currently configured to provide low latency call setup. Because the call setup latency of the wireless communication networks may be too high to provide low latency services, the communication providers may not be able to offer valuable low latency services, such as PTC services, to their customers and potential customers.